This invention relates to an automatic welding machine, and, more particularly, it is concerned with the automatic welding machine of a type which causes a welding torch to perform three dimensional locus motions by the use of three profile cams for controlling directional movements of the welding torch in the left-and-right, up-and-down, and front-and-back directions.
It is a primary object of the present invention to provide an automatic welding machine of a type, in which a welding torch supporting and moving mechanism, i.e., a driven mechanism to cause the welding torch to perform the three dimensional locus motions when it receives drive power from a driving mechanism consisting of a prime mover, profile cams, and so forth, is constructed in a freely movable manner in a relative position with respect to the driving mechanism. In such construction, it becomes possible to collectively move and position a plurality of welding torch supporting and moving mechanisms (driven section) of a plurality of same type of welding machines so as to readily effect the multi-welding operations within a limited narrow space region.
It is a secondary object of the present invention to provide an automatic welding machine of a type, wherein a driven member is connected to a cam follower member which correspondingly move in contact with a profile cam to be driven whereby, in which reinstatement of the profile cams to their original positions and their change-over from one to the other can be done easily.
It is a third object of the present invention to provide an automatic welding machine of a type, wherein forward and backward motion of a follower member is transmitted to a driven member by connecting the cam follower member correspondingly moving in accordance with the profile cam with the driven member through an inner wire in a flexible outer tube, and in which the flexible cable is prevented from buckling.
It is a fourth object of the present invention to provide an automatic welding machine of a type, in which a welding torch of a driven mechanism is automatically moved in accordance with a predetermined program of a driving mechanism, and in which the welding torch may be easily taken away from a work piece as necessity arises.
According to the present invention, in one aspect thereof, there is provided an automatic welding machine which comprises in combination: (a) a driving section including a frame to support component members thereon, a shaft rotatably held on said frame, an electric motor axially fitted at one end of said shaft, a plurality of profile cams fixedly provided on the other end part of said shaft to be rotated therewith, said profile cams being arranged with an appropriate space interval between them, cam follower members corresponding in number to said profile cams and intimately contacted therewith to move in accordance with rotational movement of said profile cams; and (b) a driven section including a frame to support component members thereon, a plurality of movable members in the left-and-right, up-and-down, and front-and-back directions in pursuance of driving force transmitted from corresponding profile cams via cam follower members in said driven section, power transmission means to transmit the driving force from each of said cam follower members in said driving section to each of said movable members in the designated direction, a welding torch slidably fitted in one of said movable member to perform up-and-down movement, said torch being fitted through a rotatable cylindrical member in said movable member, an electric motor to tilt said torch through a linking means extended between said motor and said rotatable cylindrical member.
According to the present invention in another aspect thereof, there is provided an automatic welding machine, in which the power transmission device for the movable members comprises gear means, drive shafts, and universal joints.
According to the present invention in still another aspect thereof, there is provided an automatic welding machine, in which the power transmission device for the movable member comprises a flexible cable composed of an outer tube and an inner wire inserted in said outer tube and connecting at both ends thereof said cam follower member in said driving section and said movable members in said driven section.
According to the present invention, in further aspect thereof, there is provided an automatic welding machine, in which there is further provided a hydraulic pressure cylinder to maintain said cam follower member to constantly push said profile cam to secure intimate contact between said cam follower member and said profile cam so that said cam follower member may be separated from said profile cam by inversely operating said hydraulic pressure cylinder at the time of returning of said profile cam to its original position or changing over of said cam from one to the other.
According to the present invention, in still further aspect thereof, there is provided an automatic welding machine, in which there is further provided a pulling mechanism on said cam follower member to constantly pull said cam follower toward said profile cam, and there is further provided a tensioning mechanism to impart a tension to any of the movable members in said driven section with a force which is smaller than the force imparted to pull said cam follower member toward said cam and in the direction opposite to the pulling direction, thereby imparting a constant tension to said inner wire connecting said cam follower member and said movable member.
According to the present invention, in other aspect thereof, there is provided an automatic welding machine, in which said torch is held at one end thereof on said front-and-back moving member in a manner to be able to freely determine the sliding position thereof independently of said power transmission means provided in said movable member in parallel with said torch to move said movable member.
There has thus been outlined, rather broadly, the more important features of the present invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception, upon which this disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions so far as they do not depart from the spirit and scope of the present invention.